The flowers open in the afternoon, that's where the name comes from. They stay open during the night, being pollinated by nocturnal pollinators, like the sphinx moths or hawk moths.
Also called the Marvel of Peru, the flowers of this plant are splashed with different colors, like these yellow flowers with pink- magenta spots. More interesting is that as the plant matures, it can display flowers of different colors on the same plant; the yellow flowers can change to pink or white ones change to light violet.
Four o'clock plants are shruby perennials in warm climates, growing from tuberous roots. In colder climate the foliage dies back to the ground in autumn but the tubers must be stored indoors during winter and replanted in the garden in spring.
The flowers are used for food coloring. Parts of the plant are used in herbal medicine as a diuretic and for wound healing.
Though its black seeds are poisonous, they are used as a powder in cosmetics.